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POSSIBLY EFFECTIVE

• Sexual desire. Oral Eurycoma longifolia seems to improve sexual desire.

POSSIBLY INEFFECTIVE

• Athletic performance. Oral Eurycoma longifolia does not seem to improve athletic performance in healthy persons. Details: One small study in recreational male athletes shows that taking Eurycoma longifolia 150 mg daily for 7 days before, plus one hour prior to, an endurance running trial does not increase endurance when compared with placebo (49133). Furthermore, a larger study in healthy males shows that taking a specific brand of Eurycoma longifolia extract (Physta, Biotropics Malaysia Berhad) 300 mg daily for 12 weeks does not improve physical fitness when compared with placebo (93490).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related testosterone deficiency. It is unclear if oral Eurycoma longifolia is beneficial for increasing testosterone levels in older males. Details: A clinical study in older adult males with testosterone levels below 300 ng/dL shows that taking a specific water extract of Eurycoma longifolia roots (Physta; Biotropics Malaysia) 100-200 mg daily with breakfast for 12 weeks modestly increases total testosterone levels and improves Aging Male Symptoms (AMS) and Fatigue Severity Scale (FSS) scores when compared with placebo. Improvements in testosterone are observed at 4 and 12 weeks in the 200-mg and 100-mg groups, respectively; improvements in AMS and FSS scores are observed as early as week 2 in both groups (108451). Daily food intake, exercise frequency, and other lifestyle details were not reported, limiting the validity of these findings. Another small clinical study in adults with late-onset hypogonadism shows that taking a water-based extract of Eurycoma longifolia 200 mg daily for one month seems to increase testosterone levels by about 2.6 nmol/L and improves Aging Male Symptoms (AMS) scores when compared to baseline (17924). The validity of these findings is limited by the lack of a comparator group. A meta-analysis of 5 mostly small clinical studies in healthy adult males and males with hypogonadism shows that taking Eurycoma longifolia 100-600 mg daily for 2-12 weeks modestly increases serum testosterone levels when compared with placebo (112185). However, the interpretation of this finding is limited by the heterogeneity of the included studies that utilized various dosing regimens.
• Back pain. Although there is interest in using oral Eurycoma longifolia for back pain, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Cancer. Although there is interest in using oral Eurycoma longifolia for cancer, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Diabetes. Although there is interest in using oral Eurycoma longifolia for diabetes, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Dyspepsia. Although there is interest in using oral Eurycoma longifolia for dyspepsia, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Erectile dysfunction (ED). It is unclear if oral Eurycoma longifolia is beneficial for ED. Details: A meta-analysis of two small clinical studies suggests that Eurycoma longifolia has no overall effect on erectile function based on the International Index of Erectile Function (IIEF)-5 scale (93491). However, only one of the studies in the meta-analysis included persons with known ED. This small study found that taking Eurycoma longifolia 200 mg in combination with Persicaria minor 100 mg for 12 weeks may modestly improves erectile function on Sexual Health Inventory for Men (SHIM) and Erection Hardness Scale (EHS) when compared with placebo. However, improvements in erectile function per the IIEF-5 scale were lacking (93496). Additionally, it is unclear if these effects were due to Eurycoma longifolia, Persicaria minor, or the combination.
• Hypertension. Although there is interest in using oral Eurycoma longifolia for hypertension, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Intestinal parasite infection. Although there is interest in using oral Eurycoma longifolia for intestinal parasite infection, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this purpose.
• Malaria. Although there is interest in using oral Eurycoma longifolia for malaria, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Male Infertility. It is unclear if oral Eurycoma longifolia is beneficial for improving male infertility. Details: Preliminary clinical research shows that taking a specific formulation of Eurycoma longifolia (Physta, Biotropics Malaysia Berhad) 200-300 mg daily for 3-9 months results in higher semen volume and sperm concentration, and also improves the percentage of normal sperm morphology and sperm motility, when compared with baseline (18138,93490). In one study, 15% of patients had a spontaneous pregnancy after treatment (18138). The validity of these findings is limited by the lack of a comparator group.
• Menopausal symptoms. Oral Eurycoma longifolia has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in peri-menopausal patients shows that taking a combination product (Nu-femme) containing the standardized ingredients Eurycoma longifolia (Physta, Biotropics Malaysia) 50 mg and Labisia pumila (SLP+, Biotropics Malaysia) daily for 24 weeks seems to reduce hot flashes and other menopausal symptoms when compared to baseline. However, the improvements were no better than placebo (105085).
• Muscle strength. It is unclear if oral Eurycoma longifolia is beneficial for improving muscle strength. Details: One small study in healthy male adults shows that taking Eurycoma longifolia 100 mg daily for 5 weeks in addition to participating in an intense strength training program increases muscle mass and strength when compared with those participating in strength training alone (49134). Another small study in physically active seniors shows that taking Eurycoma longifolia extract (Physta, Biotropics Malaysia Berhad) 400 mg daily for 5 weeks increases muscular force by around 15% when compared to baseline (97312). However, not all research has been positive. One small study in young, healthy males shows that taking Eurycoma longifolia 200 mg daily for 8 weeks in addition to a resistance training program does not increase isokinetic knee muscle strength or peak power when compared with resistance training alone (103619).
• Obesity. Oral Eurycoma longifolia has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A clinical study in adults with obesity following a reduced-calorie diet and performing 30-60 minutes of daily, light-intensity exercise, shows that a specific oral product (CitruSlim; NHR Science) containing Eurycoma longifolia root extract 17% and bergamot extract 83%, taken as 200 mg or 400 mg daily as three divided doses before meals for 112 days, decreases body mass index by 3.3% and 3.2%, respectively, but does not impact lipid parameters or waist-to-hip ratio, when compared with diet and exercise alone (108452). It is unclear if this effect is due to Eurycoma longifolia, bergamot, or the combination.
• Osteoporosis. Although there is interest in using oral Eurycoma longifolia for osteoporosis, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition.
• Syphilis. Although there has been interest in using oral Eurycoma longifolia for syphilis, there is insufficient reliable information about the clinical effects of Eurycoma longifolia for this condition. More information is needed to rate Eurycoma longifolia for these uses.

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POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts. Eurycoma longifolia has been safely used in doses of 400 mg daily for up to 3 months and in doses of 200 mg daily for up to 9 months (17924,18138,93490,97312).

POSSIBLY UNSAFE ...when used orally in excessive amounts, long-term. There are some concerns about the safety of Eurycoma longifolia due to contamination with mercury and lead or adulteration with sildenafil (17925,17926,17927,18137,49087,93494). Some research shows that 36% and 17% of Eurycoma longifolia preparations from Malaysia contain high levels of mercury and lead, respectively (17925,17926,17927,49087). While safety issues related to these contaminants have not been reported in humans, taking high doses of Eurycoma longifolia long-term might cause symptoms of heavy metal poisoning or sildenafil-related adverse effects.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using. Animal research suggests that there are no negative effects of Eurycoma longifolia on the offspring (93493). However, research in humans is lacking.

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CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, Eurycoma longifolia might increase levels CYP1A2 substrates.  Details In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP1A2 enzymes (93489). This effect has not been reported in humans.

CYTOCHROME P450 2A6 (CYP2A6) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, Eurycoma longifolia might increase levels of CYP2A6 substrates.  Details In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP2A6 enzymes (93489). This effect has not been reported in humans.

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, Eurycoma longifolia might increase levels of CYP2C19 substrates.  Details In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP2C19 enzymes (93489). This effect has not been reported in humans.

PROPRANOLOL (Inderal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = A Eurycoma longifolia can reduce the levels and clinical effects of propranolol.  Details A small clinical study in healthy persons shows that taking a single dose of a water-based Eurycoma longifolia extract 200 mg, in combination with a single dose of propranolol 80 mg, reduces the propranolol area under the curve (AUC) by 29%, reduces the peak concentration by 42%, and increases time to peak concentration by 86% when compared with control. Since the elimination half-life of propranolol did not change, it seems that Eurycoma longifolia alters the kinetics of propranolol by decreasing its absorption in the gut, and not by altering its metabolism (17923). It is not known if separating administration will prevent this interaction.

TESTOSTERONE Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, Eurycoma longifolia may further increase levels of testosterone.  Details A clinical study in aging males with testosterone levels below 300 ng/dL shows that taking a specific water extract of Eurycoma longifolia roots (Physta; Biotropics Malaysia) 100-200 mg daily with breakfast for 12 weeks increases total testosterone levels by 8% to 11% when compared with placebo (108451). It is unclear whether this increase would occur in individuals with normal testosterone levels.

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General ...Orally, Eurycoma longifolia seems to be well tolerated.
Most Common Adverse Effects:
Orally: None reported.

Endocrine ...Some research in both humans and animals suggests that Eurycoma longifolia might increase testosterone levels (17924). If testosterone levels are increased beyond the normal range, there is risk of testosterone-related side effects which could include acne, insulin resistance, hepatotoxicity, and others.

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